The present invention relates to a new and distinct Coreopsis and given the cultivar name ‘Buttermilk’. Coreopsis is in the family Asteraceae. This new cultivar originated from a controlled breeding program to produce hardy compact Coreopsis. The new cultivar originated from planned cross of two proprietary unnamed Coreopsis verticillata hybrid seedlings. The new cultivar of Coreopsis is an herbaceous perennial to be grown for landscape and container use in a sunny site.
Compared to the parents the new cultivar has light yellow flowers rather than yellow and/or a shorter habit.
Compared to Coreopsis ‘Star Cluster’, U.S. Plant Pat. No. 23,035, the new cultivar is denser in habit with more stems from the crown and better branching. The new cultivar has smaller flowers without a center dark star pattern.